Activities and interactions of mothers and their firstborn infants in the first six months of life: covariation, stability, continuity, correspondence, and prediction.

Activities of primiparous mothers and infants were observed at 2 and 5 months of age during naturalistic interactions at home. 5 prominent features of mother and infant exchanges in this short-term longitudinal study are described and discussed in the context of 3 models of unique environment-development relations: covariation, stability, continuity, correspondence, and prediction. Generally, mothers' activities did not positively covary at either age, nor did those of infants. Some maternal activities were stable in this time period; some developmentally increased, and some developmentally decreased. Infants' activities were unstable, but most increased over time. Specific mother and infant activities corresponded, and over time mothers and infants influenced one another in specific ways. In the critical period of the first half year, infants appear to be flexible and plastic in their behavioral repertoires and are influenced by their mothers; mothers are somewhat consistent, but they also adapt to the behaviors of their infants.